Drier



Oat. 27, 1925.

R.CATHCART DRIERK t Filed Aug. 2, 1918 3 Sheets-Sheet 2 E mi m.

Oct. 27, 1925. 1,558,835

R. CATHCART DRIER Fil'ed Aug. 2l 1918 3 Sheecs- Shee'cv 3 Patented Der.J27, 1925. I -v UNITED vSTATES. PAT

uuroFFicE.

ROBERT CATHCABT, OF CLEVELAND, Omo, 'AssIGNon To THE LINO PAINT COMPANY,or CLEVELAND, OHIO, A CORPORATION OFY OHIO'.

DRIEB.

Appneauon mea August a, 191s. serial No. 247,927.

To all whom it 'may concern.' e

Be it known that I, ROBERT CA'rHCAnT, a Vcitizen of 4the United States,residing at Cleveland, in the county of Cuyahoga and State of Ohio, haveinvented a certain new and useful Improvement in Driers, of which thefollowing is a \full.clear, and exact description. j

This invention' relates to a method and apparatus for drying, and hasparticular reference to the drying of freshly painted metal sheets andplates or other articles required to be dried.

At the present time large metal sheets and plates of various gauges andsizes, suchI as so-called black sheets, galvanized or cor- Jrugatedsheets. and other products utilized as rooting, ceiling, and sidingproducts for buildings and mechanical purposes, are painted by running'the articles betyveen paint-saturated rolls, or by dipping them in atank of paint, and are then in a rack where they remain until they aredried. Although ineffectual attempts have been made tofdry such articlesartificially, it is generally the case that they are allowed to stand onedge until dried naturally, with the result that a great deal of time isconsumed in the drying. and thc services of a number of men are requiredto handle the articles after they have been coated with paint. Oneserious disadvantage of the slow natural drying lies 4in the fact thatnot only do the drying articles require a great deal ot ioor space, butthey ofttimes become injured by contacting with the succeeding lappingsheets or articles. This necessarily not only requires a great area offloor space, but actually limits the` production.

The principal object of this invention is to provide a method andapparatus by which articles such as metal sheets and plates of the typereferred to, can be quickly dried, thus effecting a great saving of timein the drying process and eliminating the necessity for hand labor inhandling the sheets.

In accordance With my invention the sheets, plates or other articlesare. received from the paint rolls or other paint applying apparatus andcaused to pass into a cha1nber through which they are conveyed and intransit subjected to a quick drying process,

a truck or other placed .on edge and f rom which they are dischargedonto suitable conveyor. The method of and apparatus for drying thearticles in this chamber constitute the principal features of theinvention, the latter contemplating' the preheating of the articlesduring one stage of their travel, and the quick driving off of thevolatile substances or moisture, and the subsequent rapid cooling whichbrings about the tion and effective drying.

More specifically considered, the new process includes the preheating byconveying the articles through a suitably heated portion of the chamberso as to cause the evaporation of the more volatile substances orproducts such as the solvents used in the paint, and then subjecting thearticles alternately to suitably directed streams of a heating mediumsuch as hot air which further raises the temperature of the articles anddrives oil the fumes which are given olf from the plates during thepreheating stage, and

quick evaporato streams or jets of a cooling medium such as cold airwhich causes the complete evaporation and drying and .cooling so thatthe articles .may be dischargedffrom the outlet side ofl the chamber atsubstantially room temperature and in al completely dry state althoughthe time consumed in their travel from the inlet side of the chamber tothe outlet is very small, the actual time varying with the size of thearticle, but generally not in excess of three minutes, fora 30 by 7 8"plate.

Further features of the invention reside in the manner in which thepreheating, also the final heating and fume or moisture removing andsubsequent coolin `are accomplished and in the method ,O condensing theevaporated products during the cooling and drying stage. Still furtherthe invention resides in various parts and combinations of parts of theaparatus for accomplishing the results above stated.

In the accompanyingsheets of drawings wherein I have shown apparatus fordrying sheets or plates, Fig. 1 is a plan View f 2 is a transversesectional view'of-the same;

-or carrier, here shown in the form of a reel rotates, and providedalong the sides of the pit with ledges 11B and 11b on which variousparts including piping which extend lengthwise and crosswise of thechamber, are supported. At one side of the dome 10, and preferablyyextending substantially the full length thereof is an inlet opening 12for the plates or other articles to be dried, and substantiallydiametrically opposite from the inlet opening there vis a similar outletopening 13 through which the dried plates or articles are discharged.

Although other forms of conveyors may be employed as hereinafterexplained, 1n this instance there is rotatably supported in the chamberor dome by means of sultable standards atv the ends thereof, a shaft14which is preferably rotated step by step in a manner to be'hereinafter referred to, and on this shaft is a conveyor `in the form ofwhat may be termed a reel and consisting of anumber of wheelsJ15, eachcomprising a hub 15, spokes 15b and a rlm 15 carrying'a large number ofarticle supporting arms or rods 15d, each of the latter be: ing abouthalfway between a radial and tangential position. The form or type ofconveyor will depend on the form or character of articles to be dried,the present v conveyor being shown for the reason that the apparatusherein illustrated is employed for drying plates or sheets with which myinvention has especial utility. With this form of conveyor the statedposition or direction in which the arms orbxfinger 15"l extend outwardlyis of great importance and a big factor in the practical success of theinvention. The individual'plates are adapted to be sup rted between thearms 15, each plate if ong enough, beiil supported on one of the arms ofeach o these wheels.

Alongside the dome at the inlet side thereof is a frame 16 constitutinga trackway provided at the top with a series of transverse shafts -17provided with rollers 17B along which the plates are adapted to be run,this trackway being preferably positioned directly in line with thepaint applying apparatus such as paint rolls, one of which is shown inplan at 18 in Fig. 1, so that the plates after passing between the paintrolls will run along the rollers 17a to a position in front of the inletopeny which are at right angles to the rollers 17.

These rollers' 19 are normally below the ltops of the track rollers 17,but when a plate has been run onto the trackway in front of the opening12 by rocking the shaft 1'9 as by a suitable pedal mechanism, indicatedat 19c in Fig. 2, to substantially the position shown by dotted linesJin Fig. 2, these rollers 19b will pick up the plate and lncline it sothat it can slide into the dome, and by running over similar rollers 20supported by stationary arms 21 alongside the wheels 15 of the reel,these plates will be caused' to be run into the reel between two of thespokes of each wheel.

As the reel is rotated step by step, the plates will be carried each inaposition about half way between the radial and tangentlal, aroundtoward the outlet opening 13 and eventually they will engage rollers .22supported on inclined arms 23 extending lnwardly from the outlet opening13, the rollers 22 being similar to the rollers 20, and the arms 23being similar to the arms 21, in consequence of which the plates willsuccessively slide over these rollers 22 and will pass out through theoutlet opening 13 of the dome onto a suitable truck or other conveyoradapted to convey awayA the dried plates.

We come next tothe means by whichl the plates are preheated then furtherheated and freed of fumes or moisture and subsequently cooled to effectthe drying action in the manner previously briefly outlined. It will beobserved that the lower part of the dome is encircled or circumscribed'by a series of steam pipes 24, which as will be seen from Fig. 1, enterthe dome at one end, just above theledge 11, pass along one side of thedome below the inlet opening 12, then across one end of the dome, thenalong the opposite side, and then along the opposite end where theyemerge from the'dome. for the preheating stage ofthe drying process, theplates being preheated through about half their travel from the positionat which they enter the reel tothe position at which they leave thereel. In other words for about 90 of movement since the plates leave thedome at a point about diametrically oppositefrom the point at which theyenter the dome. k

During this preheating stage the plates are not subjected to a blast ofair as they are subsequently, but they are heated by the heated airwhich rises from the steam heated pipes 24 andpasses'out through theThese 'steam pipes heat the air,

' 0f the dome (see Fig. 2),

assassin top of the dome in the manner hereinafter described. It isduring this period that the more volatile materials of the paintedplates are evaporated. This forms fumes, the major portion of which inpractice cling to the rotating plates, until the plateslreach a certainposition. l

l/Vhile I have shown steam pipes for producing the heat for thepreheating step of the process, I do not wish to be coniined to steampipes as other means might be employed for this purpose. f

Next the preheated plates are subjected to the action of t heatingmedium preferably a blast of heated air after having traveled throughabout half their movement or through an arc of about 90", as beforestated. This hot air blast is provided by a series of branch pipes 25,the outlet ends of which'are near the shaft 14 and between the wheelsforming the plate supporting and rotating reel. It will be observed byreference to bothFigs. 1 and 2 that these branch pipes 25 extendupwardly and inwardly from a relatively large hot air feed pipe 26 whichis just above the ledge 11n and is surrounded by the steam pipes 24where they extend along the inlet side of the dome, The heated air issupplied by a suitable fan, 26a shown in Figs. 3 and 4, and the air ispreferably heated by passing it through heating coils 26" (Fig. 3) whichmay be steam heated, though the steam pipes 24 may be relied on for thispurpose since the arrangement shown at the left hand side of Fig. 2 issuitable for heating the air in pipe 26.

Extending from the top of the dome are a series of branch hot airexhaust pipes 27, each with a damper 2S which is near the top whichpipes are connected to a main exhaust pipe 29 which may and preferablyis connected to the inlet side of the fan 26a which circulates the airthrough the hot air pipe 26 so that there will. be a continuouscirculation.

The effect of subjecting the plates to the hot air blast through thepipes Qis to still further raise the temperature of he plates over thetemperature to which the plates were gradually raised in passing throughthe preheating stage, and afurther effect is to blow off of and frombetween the plates the fumes or gases formed by the evaporation of themore -volatile materials such as the solvents utilized in the paint. Thehot air and these fumes pass out from the top of the dome through thepipes 27 and 29, the major portion of the fumes being condensed afterthey leave the dome and before the air is again reheated andrecirculated back through the dome by way of the pipe 26 and branchpipes25. However, the condensate at this point is very small, and nomeans need be provided for toward the pit in view o removing it aspractice has demonstrated,

and no special condenser is needed as the moisture condenses by comingin Contact pipes which are cold air pipes 30 which extend legthwise ofthe dome it being immaterial whether they extend outside or insidethedome, but

preferably outside, as here shown, justabove the outlet opening 13,andwhich will be best seen by reference to Fig.Y 2. Each of these cold airpipes 30 has a series of outlets on nozzles 31 which extend downwardlyand inwardly through the wall of y the dome so that the cold air will bedirected onto the plates shortly after they pass beyond the streams ofair supplied by the hot air pipes 25. This quickly cools the plates andalmost instantaneously dries them. The air may be supplied to the pipes30 by any suitable means, such as by a fan 30E, shown in Figs. 3 and 4.After a short further movement they engage the rollers 22 andautomatically slide out from the dome through the outlet opening 13 ontoa truck or other device provided to receive the plates, and when theypass from the dome they are thoroughly dried and at a temperaturecorresponding almost precisely with the room temperature.

The cold air utilized in cooling and drying the plates after leaving thelatter nearly saturated with moisture,

the fact that it is much heavier than the heated air, and in passingdownwardly comes in contact with cooling pipes 32 which may be watercooled and which extend transversely across the chamber beneath theshaft 14. as best shown in Fig. 2. Most of the moisture carried awayfrom the plates by the downwardly passing air currents is condensed onthese pipes and drops to the bottom of the chamber. A suitable outlet 31may be provided for draining oil' liquid accumulating in the bottom ofthe tank. The water is supplied to and i. conveyed away from' the pipes32 passes downwardly by a water supply pipe 33 and a-water exe 34, thesepipes extending alongome, one on one side and one on the the reel.Between the Ipulley and worm wheel gearing is a clutch shownconventionally at '37. 'This clutch can be and preferably is operated bysuitable mechathe chamber, said pedal 37 bein'g connected by "a rod 37bWith a suitable clutch shifter 37 for shifting the clutch 37, as shownin Figs. l and 2. In this manner the plates can be fed into the chamberand into the reel, and the reelfcan be turned' step'by step as fast -asthe plates can be run through plate as it emerges is completely driedand the paint rolls, and as .the step by step movement is given to thereel rapidly, the reel is given substantially a half Y rotationsuiiicient to carry aplate from the inlet side, Ato the outlet side in avery brief space of time. But in this short space'oftime each cooled tosubstantially room temperature, the temperature of the lates as theyemerge from the chamber rarely varying more than a degree from roomtemperature.' However, the temperature at which the `articles emerge inany particular installation depends on the character of the articles andthe temperatures of the heating and cooling media.

l' lhus it will be seen that With-this process an enormous saving` oftimeis eliect'edfin' the drying operation and4 that the necessity for ahuge floor space heretofore utilized for the Aracks of drying plates isentirely. eliminated. LFurthermore, aside fro the fact that one operatormanipulates foot pedals to cause the plates to enter the chamber and thereel to be moved through a predetermined arc, the whole operation is'automatic, itbing'unnecessary for laborers to pick up or handle theplates'as has hereto-` ore been necessary.

This method of drying is operative regardless of Weather conditions bothas to temperature and moisture-the same speed and the same dryingeffects being obtainable incold Weather as Warm weather, and when thehumidityis high as yvell as When it is 10W, it being only necessary'A tadjust the apparatus to suit the weather conditions. This adjustment '6radjustments include the adjustment or variation of the quantity andtemperatures of the hot and cold air and the manipulationof the dampers28 to increase or decrease the'ireedom of movement of the heated airfrom the top of the dome. I have -not shown the valves for varying thefl'ovv of hot and cold air, northe means for varying the temperature ofthe air, but it will be obvious that such devices'vvill be providedWherever necessary, to adapt the apparatus and the method for allconditions including Weather' conditions and the conditions of thearticles to be dried With respect to moisture.

Other ways of carrying out the principle of my invention may occur toone skilled in the art, and I aim in my claims to cover all modicationsand'changes which do not involve a departure from the s irit and scopeof my invention in its broa est aspects.

Having described my invention, I claim:

1.1The method of drying articles which comprises conveying them with anarcuate movement through a chamber, `and While so doing passingthearticles successively through streams of 'heating `and cooling media.`

2'. The method of drying articles which comprises preheating thearticles and then successively subjecting theml to the action of .aheating medium which heats the articles more rapidly than in thepreheating stage and still further raises their temperature,

and to the action of a cooling medium. s

the heating-medium increasing the temperature of the articles over thatreached in the preheating stage and heating them more rapidly'than inthe preheating stage.

4. The method which comprises conveying articles-through a chamber andin transitu drying the same by car ing the articles first through aheated' portlon ofthe chamber, then' through a stream of 'a relativelyfast moving heating medium which further elevates the temperature ofthearticles, and then through a stream of a cooling medium. 5'. The methodof' drying articles which comprises passing them through a chamber firstthrough aspreheating stage -where the tem erature of the articles israised to a pre etermined` point by `a relatively still 105 dium andthen a flowing cooling medium,

and then through a stagerwliere 'the articles 110 are subjected to theaction' of a cooling medium. f' e 6. In anapparatus' for dryingarticles, a chamber having an inlet side and an outlet side, means forconveying the articles from 1 the former to vthe latter with an arcuatemovement,'and .means forsupplying to the chamber heating j and coolingmedia through which the articles are successively passed.

7. In a drying apparatus, a chamber havl ing an inlet side andan outletside, a device for conveying the articles, from the former to thelatter, means for heating a portion of the chamber toward the inletside, and additional means for supplying a heating me- `diumand'acooling medium through which distance therefrom an'outlet opening,a con- 1 0 veyor in the :form of a rotary reel adapted to receive thearticles when inserted through the'inlet' side and to discharge thearticles through the outlet side, and means whereby the articles whiletraveling through the chamber are alternately heated and then cooled anddried. i

9. -In an apparatus for drying articles, a chamber having an inletopening and at a distance therefrom an outlet opening, a conveyoradapted to receive theh articles when inserted through the inlet sideand to discharge the articles through the outlet side, means forpreheating the articles as they pass from the inlet side, and means forsupplying to the chamber streams of a heating medium and of a coolingmedium through which the articles are successively passed after beingpreheated.

10. In an apparatus for drying articles, a chamber having at one pointan inlet opening for the articles, and at .a different point an outletopening, a conveyor for supporting and conveying the articles from theinlet opening to the outlet opening, means for heating one side of thechamber, means for causing a heating medium to be directed onto thearticles to be dried, and means for causing a cooling medium to bedirected onto the articles to be dried, said articles being alternatelyconveyed through the heated portion, through the heating medium andthrough the cooling medium.

11. In a drying apparatus, a chamber having an inlet opening at onepoint and an outlet opening at a different point, a conveyor forconveying articles from the inlet point to the outlet point, heatingmeans eX- tending adjacent the inlet point, means for conveying aheating medium and for discharging the same onto the articles carried bythe conveyor while passing through a predetermined portion of their pathof movement, means for directing a cooling medium onto the articlesafter passing from the. heating medium, and an outlet at the top of thechamber. U A

l2. In a drying apparatus, a chamber d having an inlet opening at onepoint and an outlet .opening ata different point, a conveyor forconveying articles from the inlet point -to the outlet point, meansI forheating'a portion of the chamber interior through which the articlesinitially pass, means for conveying a heating medium and for dischargingthe same onto the articles carried by the conveyor while passinglthrough another portion of their movement, means for directing a coolingmedium onto the articles after passing from the heating medium,andmoisture condensing means in the chamber.

13. In a drier, a chamber, a rotary carrier in the chamber havingoutstanding fingers arranged between the radial and tangential positionsand adapted to receive between them articles to be dried, and meanswhereby the articles are successively heated and cooled while beingcarried by the 'carrier through the chamber. I

14. In a drier, a-chamber having openings for the admission'alidWithdrawal of arti. cles, a carrier .in vthe chamber Ihaving outstandingiingers between which articles to be dried are adapted to be inserted,

and means for subjecting the articles. while being conveyed by thecarrier from' the admission to the withdrawal openings,

alternately to streams pf a heating medium anda cooling medium.

15. In a drier,

for the admission and withdrawal of articles to be dried, a carrier forconveying the artip cles through the chamber, means for heating thearticles as they are conveyed through the chamber, means for subjectingthem to the action of a cooling medium before the artia chamber havingopenings cles reach the withdrawal opening of the chamber, and means inthe chamber for condenslng the moisture 1n sa1d medium after coming 1nContact with and cooling the artif cles.

16. Ina drier, achamberhaving a conveyor for conveying articles to bedried, i

18. The method of drying articles which comprises conveying the articlesthrough a chamber, heating the articles, andv then cooling the articlesby directing' a cooling medium on the articles in a' predetermineddirection with respect to their surfaces.

19. The method of drying articles which comprises conveying them'through a chamber, and alternately subjecting them to the action ofaheating medium and tothe action of a pooling medium with each mediumdirected onto the articles in a predetermined direction with referenceto the surfaces and path of movement of the articles. 1

20LfIn a drier, a chamber arc-shaped in cross-section, va conveyor forconveying articles to be dried from one part of thechamher to anotherwith an arcuate movement, andi"25 comprises conveying the articlesthrough a;

chamber, with the articles arranged 1n a p ma f 6A v1,558,885

v predetermined position with respect to one While thus conveyed heatingthe articles and "another, `and first heating them and then `thencooling them, the cooling medium being cooling them, the heating mediumbeing directed in the form of a stream soas to directed in the form of astream along the vpass along the surfaces of the articles and Iarticlesv and in a particular direction with in a given-directionwithreference to their 15 respect Ato the angle of repose of saidarticles. angle of repose.V

22. The method of drying articles which In testimony whereof, I hereuntoaiiix my n comprises conveying -the articles through a signature. r.

chamberwhile arranged in a. predetermined l0 relation 4with respect toone another, and f l I ROBERT CATHCART.

